Pheochromocytoma differential diagnosis
|
Pheochromocytoma Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Pheochromocytoma differential diagnosis On the Web |
|
American Roentgen Ray Society Images of Pheochromocytoma differential diagnosis |
|
Risk calculators and risk factors for Pheochromocytoma differential diagnosis |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmad Al Maradni, M.D. [2]
Please help WikiDoc by adding content here. It's easy! Click here to learn about editing.
Overview
Pheochromocytoma must be differentiated from anxiety, carcinoid, and hypoglycemia.
Differentiating Pheochromocytoma from other Diseases
DIFFERENTIAL DIAGNOSIS — In addition to pseudopheochromocytoma, the following diagnoses should be strongly considered among patients presenting with paroxysmal hypertension:
●Pheochromocytoma
●Labile hypertension
●Panic disorder
Pheochromocytoma — The diagnosis of pheochromocytoma must be excluded in all patients with unprovoked paroxysmal hypertension. Assays of plasma or urine catecholamines are diagnostic in 95 percent of patients with symptoms, and the high sensitivity of the plasma metanephrine assay is also documented [12-14]. Although there is still uncertainty as to the "best" test [12,13,15], most patients with clinically evident pheochromocytoma have very abnormal, rather than mildly abnormal, values. (See "Clinical presentation and diagnosis of pheochromocytoma".)
Labile hypertension — A clear relationship between blood pressure elevation and stress or emotional distress is usually evident among patients with labile hypertension. Patients know they are upset and blame the hypertensive episodes on emotional distress. By contrast, patients with pseudopheochromocytoma insist that the disorder is unrelated to psychologic factors.
Panic disorder — Panic disorder is characterized by episodes of fear or panic, and is commonly associated with physical symptoms such as chest pain, headache, palpitations, flushing, and dizziness, along with some degree of blood pressure elevation [16-20]. Panic disorder and pseudopheochromocytoma share similar physical symptoms, and both respond to treatment with an antidepressant agent. As mentioned above, panic disorder is present in as many as 40 percent of patients evaluated for pseudopheochromocytoma, compared with 5 percent of control patients with hypertension [3], and, in one report, panic disorder presented as paroxysmal hypertension [21].
However, the two disorders differ from each other in that the presentation of pseudopheochromocytoma is dominated by autonomic manifestations (ie, paroxysmal hypertension). In patients with pseudopheochromocytoma, fear occurs only in response to the physical symptoms. By contrast, panic disorder is dominated by emotional manifestations (ie, panic), and accompanying blood pressure changes are milder.
The most critical clinical difference is that, in the absence of antecedent panic or emotional distress, pseudopheochromocytoma is viewed as an unexplained medical disorder. Therefore, clinicians and patients rarely consider an emotion-based cause or treatment because, by definition, patients fail to report any triggering emotional distress.
Other causes of paroxysmal hypertension — Many additional disorders may present with paroxysmal hypertension, including the following:
●Anxiety.
●Hyperthyroidism (see "Overview of the clinical manifestations of hyperthyroidism in adults").
●Cluster or migraine headaches (see "Cluster headache: Epidemiology, clinical features, and diagnosis" and "Pathophysiology, clinical manifestations, and diagnosis of migraine in adults").
●Hypertensive encephalopathy (see "Moderate to severe hypertensive retinopathy and hypertensive encephalopathy in adults").
●Coronary insufficiency.
●Renovascular hypertension (see "Evaluation of secondary hypertension").
●Central nervous system lesions, such as stroke, tumor, hemorrhage, compression of lateral medulla, and trauma (see "Clinical diagnosis of stroke subtypes").
●Seizure disorder.
●Carcinoid (see "Clinical features of the carcinoid syndrome").
●Drugs – cocaine, lysergic acid diethylamide, amphetamine, and clozapine [22].
●Tyrosine ingestion combined with monoamine oxidase inhibitors.
●Baroreflex failure, which is characterized by marked and frequent fluctuations in blood pressure, with both high and low readings [23]. It is caused by hypofunctioning of the baroreflexes that normally buffer blood pressure fluctuations. The disorder is usually a result of injury to carotid baroreceptors, with most patients reporting a history of neck irradiation or surgery.
●Factitious hypertension.
Such disorders must be considered when suggested by the history, physical examination, and/or diagnostic studies [1]. However, such causes are uncommon among patients with recurrent paroxysmal hypertension.
The differential diagnosis of pheochromocytoma includes:
- Anxiety disorders
- Carcinoid tumor
- Paragangliomas
- Essential hypertension
- Hyperthyroidism
- Insulinoma
- Paroxysmal supraventricular tachycardia
- Renovascular hypertension
- Hypoglycemia
- Stress
- Exercise
- Medications such as stimulants, methyldopa, and dopamine agonists
Sympathomimetic drugs that can induce symptoms simulating pheochromocytoma include high-dose phenylpropanolamine (a popular over-the-counter decongestant and appetite suppressant), cocaine, amphetamines, phencyclidine, epinephrine, phenylephrine, and terbutaline, and the combination of a monoamine oxidase (MAO) inhibitor and ingestion of tyramine-containing foods [7,26-29]. Mercury intoxication also can mimic pheochromocytoma, producing both hypertension and elevated urine and plasma catecholamines [30].
Panic disorder can replicate many of the symptoms of pheochromocytoma because it is associated with increased sympathetic activity. Hypertension in these patients occurs primarily during treatment with a tricyclic antidepressant drug, which may increase the degree of sympathetic arousal.
The potential importance of this disorder in the differential diagnosis of pheochromocytoma was illustrated in a study in which 300 adults were referred for possible pheochromocytoma .